In a focal-plane shutters for carrying out exposure of an imaging element or film through opening/closing an opening portion (frame) through a blade group, there are those that are structured such that a blade group that is disposed in a blade chamber that is formed between a base plate and a supplementary base plate is driven by a driving mechanism portion so as to change the state of opening/closing of the opening portion so as to carry out exposure. In such focal-plane shutters, the driving mechanism portion and the blade group are linked through a blade arm by a blade dowel, or the like. When the focal-plane shutter is operated, the blade dowel of the blade arm is operated while in contact with the shutter base plate or supplementary base plate, or the like, and thus the blade dowel becomes worn by the friction during operation. Japanese Unexamined Patent Application Publication 2004-325553, for example, discloses a technology for performing a plating process, such as nickel plating, on the blade dowel in order to prevent such wearing of the blade dowel.